Tradesmen, I've gathered, ultimately want publicity (13)

I believe the answer is:

'publicity' is the definition.
(advertisement is a kind of publicity)

'tradesmen i've gathered ultimately want' is the wordplay.
'gathered' indicates anagramming the letters.
'ultimately' says to take the final letters.
The last letter of 'want' is 't'.
'tradesmen'+'ive'='tradesmenive'
'tradesmenive' is an anagram of 'advertisemen'.
'advertisemen'+'t'='ADVERTISEMENT'

(Other definitions for advertisement that I've seen before include "Public promotion" , "Bill" , "Commercial promotion" , "trailer" , "Publicity announcement" .)

I've seen this clue in The Times.

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